A method has been developed for surface modifications of high temperature resistant alloys, such as FeCrAl alloys, in order to increase their resistance to corrosion at high temperatures. Each class or set of symbols includes one or more related symbols. Tipping of the flowerpot assembly brings the wheels into contact with the surface, and further tipping frees the bottom of the pot from contact with the surface. The electronic control unit includes a housing in which are mounted a circuit board and other electronic and electric parts, and a fitting portion provided on the housing so as to face one side of the block. The system is adapted to provide wireless Data Network Telephony, and the hand-held communicators execute Quality of Service code adapted to prioritize DNT packet code over all non-DNT traffic, thereby preserving the real-time nature of the DNT code.